The comparative effects of metabolic surgery, SGLT2i, or GLP-1RA in patients with obesity and type 2 diabetes: a retrospective cohort study

Background: New antidiabetic agents (sodium-glucose cotransporter-2 inhibitor [SGLT2i] and glucagon-like peptide-1 receptor agonist [GLP-1RA]) and metabolic surgery have protective effects on metabolic syndromes. Objectives: To compare the changes of metabolic parameters and costs among patients with obesity and type 2 diabetes undergoing metabolic surgery and initiating new antidiabetic agents over 12 months. Setting: Hong Kong Hospital Authority database from 2006 to 2017. Methods: This is a population-wide retrospective cohort study consisting of 2,616 patients (1,810 SGLT2i, 528 GLP-1RA, 278 metabolic surgery). Inverse probability treatment weighting of propensity score was applied to balance baseline covariates of patients with obesity and type 2 diabetes who underwent metabolic surgery, or initiated SGLT2i or GLP-1RA. Metabolic parameters and direct medical costs were measured and compared from baseline to 12 months in bariatric surgery, SGLT2i, and GLP-1RA groups. Results: Patients in all 3 groups had improved metabolic parameters over a 12-month period. Patients with metabolic surgery achieved significantly better outcomes in BMI (-5.39, -0.56, -0.40 kg/m2, p<0.001), % total weight loss (15.16%, 1.34%, 1.63%, p<0.001), systolic (-2.21, -0.59, 1.28 mmHg, p<0.001) and diastolic (-1.16, 0.50, -0.13 mmHg, p<0.001) blood pressure, HbA1c (-1.80%, -0.77%, -0.80%, p<0.001), triglycerides (-0.64, -0.11, -0.09 mmol/L, p<0.001), and estimated glomerular filtration rate (3.08, -1.37, -0.41 ml/min/1.73m2, p<0.001) after 12-month compared with patients with SGLT2i and GLP1-RA. Although the metabolic surgery group incurred the greatest direct medical costs (US$33,551, US$10,945, US$10,627, p<0.001), largely due to the surgery itself, the total monthly direct medical expenditure of metabolic surgery group became lower than that of SGLT2i and GLP1RA groups at 7 months. Conclusions: Beneficial weight loss and metabolic outcomes at 12-months were observed in all 3 groups, among which the metabolic surgery group showed the most remarkable effects but incurred the greatest medical costs. However, studies with a longer follow-up period are warranted to show long-term outcomes